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I believe conversion factors have an infinite number of significant figures. They should be exact values; but not all of them are, are they?
I looked at [a pdf document](http://www.webassign.net/question_assets/buelemphys1/chapter01/section01dash2.pdf) ([via the Internet Archive](https://web.archive.org/web/20181223... |
Do all conversion factors have an infinite number of significant figures? |
> Given the two reduction half-reactions for the following fuel cell, determine the standard cell potential $E^\circ_\mathrm{cell}$,
$$\ce{CH4 (g) + 2 O2 (g) + 2 OH- (aq) -> CO3^2- (aq) + 3 H2O}.$$
Reduction half-reactions:
\begin{align}
\ce{CO3^2- (aq) + 7 H2O (l) + 8 e- &-> CH4 (g) + 10 OH- (aq)}&
E^\circ &= \pu... |
I am trying to determine how much sodium dichloro-s-triazinetrione dihydrate powder I should add to water to create a dilution that can be injected into my water supply to react with the Hydrogen Sulfide and remove it.
I have a system in my home that uses sodium hypochlorite (bleach) and water. There is a 30 gallon ... |
How much of Sodium dichloro-s-triazinetrione dihydrate should I use to replace bleach? |
I'm in an introductory Chemistry class and ran into a Pearson problem, that no-one in our class including our professor has been able to truly figure out.
I know the solution is $4.69 * 10^{13}$.
Attached are images.
[![enter image description here][1]][1]
[![enter image description here][2]][2]
[... |
My question concerns how energy is used in chemical reactions. I am working with a reaction between magnesium and hydrochloric acid (although this is not a homework question). What I've found is that the magnesium gives away its valence electrons to either the hydrogen or to the chloride. But in the second case, the ch... |
My question concerns how energy is used in chemical reactions. I am working with a reaction between magnesium and hydrochloric acid in a class (although this is not a homework question). What I've found is that the magnesium gives away its valence electrons to either the hydrogen or to the chloride. But in the second c... |
Molecule with reversible exothermic conformational change? |
Well, the solution enthalpy of sugars is positive.
I found these numbers on the internet
* C12H22O11 (sugar(saccharose?)) 5.4 kJ/mol
* C6H12O6 11 kJ/mol
* C6H12O6·H2O (glucose monohydrate) 19 kJ/mol
But your "energy drink" is already a solution, so this wont explain much. |
Well, the solution enthalpy of sugars is positive.
I found these numbers on the internet
* C12H22O11 (sugar(saccharose?)) 5.4 kJ/mol
* C6H12O6 (glucose) 11 kJ/mol
* C6H12O6·H2O (glucose monohydrate) 19 kJ/mol
But your "energy drink" is already a solution, so this wont explain much. You should put a thermome... |
The likely issue is the presence of any water (which can also be sourced as you noted by the heating of NaHCO3).
[Here is a source](https://www.mdpi.com/2073-4441/3/1/235/htm) to quote:
>The radiolysis of water due to ionizing radiation results in the production of electrons, H● atoms, ●OH radicals, H3O+ ions and... |
It's to my understanding that sulfur can form 6 bonds because of its ability to reach into the d orbital. What's stopping it from forming structures like that of carbon in a diamond? |
Why isn't S7 a molecule? |
I learnt from my textbook and the question/answer - *https://chemistry.stackexchange.com/q/19001/81509* that active mass of a solid or liquid is taken to be unity as:
$$\text{Active mass} = \frac{\text{Number of moles}}{\text{Volume}}=\frac{\text{Mass}}{\text{Molar mass}\ \times \ \text{Volume}}=\frac{\text{Density}... |
Is the active mass of every solid and liquid taken to be unity? |
When mixed with water how does gypsum act as a binder in creating concrete? |
How does Gypsum Concrete work? |
So there is this question which asks whether the following complex
> $\ce{[Co(NH3)4Br2]+}$
will show optical isomerism or not.
According to my knowledge it will show optical isomerism in cis form only and not in trans form so overall the compound shouldn’t be optically active.[![enter image description here][... |
[![enter image description here][1]][1]
[1]: https://i.stack.imgur.com/BuGDf.png
Hello!
In this textbook example question, how come the chlorine reaction, which has the greatest reducing power will not react? If it has the greatest E of 1.36 V that means it has most reducing stength and can "pull" electro... |
I am making a sensor to sense the change in concentration of NaCl. My background is in electronics and chemistry is not my strong area. I got some screen printed electrodes, with Silver (Working Electrode) and Ag/AgCl (Reference Electrode). My initial test is to put the electrodes in separate solutions, with Reference ... |
This will work with the correct set up. You're constructing a galvanic cell, which will result in a cell voltage. The cell voltage will change when you alter the concentration of NaCl on either side. Important though that your two half cells (each side) are connected both electronically and ionically. Do you have a sal... |
How many deuterium atoms (symbol D for deuterium) are present in $\pu {3.00 x 10^{-6} g}$ of water?
Answer:
$$\pu{3.00 x 10^{-6} g} \;\ \ce{H2O} \times \frac{\pu{1 mol} \;\ce{H2O}}{\pu{18.015 g} \;\ce{H2O}}\times \frac{\pu{2 mol} \;\text{H}}{\pu{1 mol} \;\ce{H2O}}\times 0.000156 \times \frac{\pu N_A \;\text{D ato... |
Is using the term "family" strictly correct when we mean a group of the periodic table or is it just in general use (and should perhaps be discouraged in favour of using "group" exclusively)? At my highschool, other teachers refer to the transition metals as a family; is this a common practice? |
Is "family" synonymous with "group"? |
Why dissolving sodium hydroxide in water is an exothermic process. What causes the evolution of heat when dissolving sodium hydroxide in water? |
Reason for Exothermic reaction? |
According to a relevant reference (Ref.1) Following reactions happen when sodium hypochlorite and sodium dichloro-s-triazinetrione dissolve in water, respectively:
$$\ce{NaOCl + H2O -> HOCl + NaOH} \tag {1}$$
$$\ce{NaCl2(NCO)3 + 2 H2O <=> 2 HOCl + NaH2(NCO)3} \tag {1}$$
Hence it is safe to assume that you need... |
According to a relevant reference (Ref.1) Following reactions happen when sodium hypochlorite and sodium dichloro-s-triazinetrione dissolve in water, respectively:
$$\ce{NaOCl + H2O -> HOCl + NaOH} \tag {1}$$
$$\ce{NaCl2(NCO)3 + 2 H2O <=> 2 HOCl + NaH2(NCO)3} \tag {1}$$
Hence it is safe to assume that you need... |
According to a relevant reference (Ref.1) Following reactions happen when sodium hypochlorite and sodium dichloro-s-triazinetrione dissolve in water, respectively:
$$\ce{NaOCl + H2O -> HOCl + NaOH} \tag {1}$$
$$\ce{NaCl2(NCO)3 + 2 H2O <=> 2 HOCl + NaH2(NCO)3} \tag {1}$$
Hence it is safe to assume that you need... |
How many deuterium atoms (symbol D for deuterium) are present in $\pu {3.00 x 10^{-6} g}$ of water?
Answer:
$$\pu{3.00 x 10^{-6} g} \;\ \ce{H2O} \times \frac{\pu{1 mol} \;\ce{H2O}}{\pu{18.015 g} \;\ce{H2O}}\times \frac{\pu{2 mol} \;\text{H}}{\pu{1 mol} \;\ce{H2O}}\times 0.000156 \times \frac{N_\mathrm A \;\text{D... |
According to a relevant reference (Ref.1) Following reactions happen when sodium hypochlorite and sodium dichloro-s-triazinetrione dissolve in water, respectively:
$$\ce{NaOCl + H2O -> HOCl + NaOH} \tag {1}$$
$$\ce{NaCl2(NCO)3 + 2 H2O <=> 2 HOCl + NaH2(NCO)3} \tag {1}$$
Hence it is safe to assume that you need... |
I use methane gas for cooking and there are times in which, despite burners being clean,
the flame doesn't burn that well and/or is quite red.
I suspect that said gas actually has some air added in, either intentionally as a fraud or not,
and would like to test for its purity.
Are there any ways I'd check this?
... |
How to test for methane gas purity? |
Determine H, q, w, and E at 298 K and 1 atm for the complete reaction of 8.170 g of N2O4.
N2O4(g) + 2N2H4(l) 3N2(g) + 4H2O(l).
The heat of formation of liquid hydrazine (N2H4) is 50.63 kJ/mol. Use tabulated data for other heats of formation.
The tolerance on each question is only 0.03 kJ, so express all answer... |
Determine H, q, w, and E at 298 K and 1 atm for the complete reaction of 8.170 g of N2O4.? |
> Determine $H$, $Q$, $W$, and $E$ at $298\ \mathrm K$ and $1\ \mathrm{atm}$ for the complete reaction of $8.170\ \mathrm g$ of $\ce{N2O4}$.
> $$\ce{N2O4(g) + 2N2H4(l) -> 3N2(g) + 4H2O(l)}$$
> The heat of formation of liquid hydrazine ($\ce{N2H4}$) is $50.63\ \mathrm{kJ/mol}$. Use tabulated data for other heats o... |
What is the result of the combustion of the mixture? |
Ozone is a bent molecule, and therefore, Ozone is a polar molecule.
Polar molecules have dipole-dipole intermolecular forces.
CO2 is a linear molecule, and therefore, CO2 is a nonpolar molecule.
Nonpolar molecules have london dispersion intermolecular forces.
Having dipole-dipole intermolecular forces means you ... |
Which has a lower boiling point, Ozone or CO2? Why? |
An oxidizing agent pulls the electron cloud of the substance being oxidized towards itself, for example:
$$\ce{F2 + 2 X- -> 2F- + X2}\qquad (\ce{X} = \ce{Cl}, \ce{Br}, \ce{I})$$
We also know that fluorine has very high charge/mass ratio as it is very small in size
and its electron gain enthalpy is know to be... |
The current question is inspired by this existing question: https://chemistry.stackexchange.com/questions/34503/at-what-frequency-does-a-non-polar-molecule-acquire-a-dipole-able-to-participate?rq=1. In the comments and answers, it says that there is always a dipole (but the time-average of these dipoles is zero), so it... |
When non-polar particles interact through dispersion forces, how fast does a temporary dipole induce a dipole in the neighboring molecule? |
I'm not a chemist but am trying to make a product to be used as a foliar spray on turfgrass for my own use. The product I'm trying to make is:
12% Humic Acid (pH 3.5-4.0)
2% Fulvic Acid (pH 9.6)
6% Kelp Extract
0.5% Salicylic Acid
79.5% Water (local sourced water pH is 6.8-7.5)
I'd like to make this in 19L (... |
I found out that diamonds consist entirely of carbons single bonded to other carbons, and it made me curious as to what other elements could form the same structure. Silicon came to mind, being in the same group as Carbon, but I believe I read about it being too big to form the structure of a diamond.
The next eleme... |
Can a Sulfur Atom Form Six Hydrogen Bonds With Six other Sulfur Atoms? |
I found out that diamonds consist entirely of carbons singly bonded to other carbons, and it made me curious as to what other elements could form the same structure. Silicon came to mind, being in the same group as Carbon, but I believe I read about it being too big to form the structure of a diamond.
The next eleme... |
Can a sulfur atom form six single bonds with six other sulfur atoms? |
In order to determine the relative stabilities of resonance structures, my textbook gives the following rules (in order):
1. The more covalent bonds a structure has, the more stable it is.
2. Structures in which all of the atoms have a complete valence shell of electrons (i.e., the noble gas structure) are espe... |
How to determine the relative stability of resonance structures when different rules give contradictory outcomes? |
Ethyl alcohol is widely used on beverages, while isopropyl alcohol is commonly sold as an antiseptic. However, some use ethyl alcohol and isopropyl alcohol as both antibacterial protection.
I am curious on which of the two alcohols will provide better antibacterial protection? Does the chemical structure of the alc... |
While reading about cis/trans isomerism in cycloalkenes, I came across the following statement:
When the number of carbon atoms in a cycloalkane is less than 11, the cis form is more stable than the trans form. When it is greater than 11, the trans form is more stable than the cis form.
An obvious question came... |
Which form would be more stable - cis or trans - when the number of carbon atoms in a cycloalkene is "equal" to eleven? |
I'm in an introductory Chemistry class and ran into a Pearson problem, that no-one in our class including our professor has been able to truly figure out.
I know the solution is $4.69 \times 10^{13}$.
Attached are images.
[![enter image description here][1]][1]
[![enter image description here][2]][2]
... |
**Background**: I am trying to get an overview of the data-processing pipeline for solving protein structures by x-ray crystallography, and understand what mathematical procedures that are conducted (and when in the process). I find it a bit confusing as both textbooks and information on the internett seem to either gi... |
Is cis- or trans-cycloundecene more stable? |
**Background**: I am trying to get an overview of the data-processing pipeline for solving protein structures by x-ray crystallography, and understand what mathematical procedures that are conducted (and when in the process). I find it a bit confusing as both textbooks and information on the internett seem to either gi... |
**Background**: I am trying to get an overview of the data-processing pipeline for solving protein structures by x-ray crystallography, and understand what mathematical procedures that are conducted (and when in the process). I find it a bit confusing as both textbooks and information on the internett seem to either gi... |
Let's start with your statement that "dissolving sodium hydroxide in water is an exothermic process." I assume it is based on the reported standard enthalpy of solvation, which is $-44.2$ kJ/mol.
If you go into the lab and try to make a 1 M solution of sodium hydroxide, however, you'll find that the solution gets ... |
I'm not a chemist but I am trying to make a product to be used as a foliar spray on turfgrass for my own use. The product I'm trying to make is:
- 12% Humic acid ($\mathrm{pH =}$ 3.5-4.0)
- 2% Fulvic acid ($\mathrm{pH =}$ 9.6)
- 6% Kelp extract
- 0.5% Salicylic acid
- 79.5% Water (local sourced water $\math... |
I am currently studying the textbook *Physics of Photonics Devices, Second Edition*, by Shun Lien Chuang. In a section discussing the **basic concepts of semiconductor band and bonding diagrams**, the author gives the following description:
> The basic idea is that for a semiconductor, such as $\ce{GaAs}$ or $\ce{... |
**Background**: I am trying to get an overview of the data-processing pipeline for solving protein structures by x-ray crystallography, and understand what mathematical procedures that are conducted (and when in the process). I find it a bit confusing as both textbooks and information on the internett seem to either gi... |
Ethyl alcohol is widely used in beverages, while isopropyl alcohol is commonly sold as an antiseptic. However, some use both ethyl alcohol and isopropyl alcohol as antibacterial protection.
I am curious to know which of the two alcohols will provide better antibacterial protection? Does the chemical structure of th... |
**Background**: I am trying to get an overview of the data-processing pipeline for solving protein structures by x-ray crystallography, and in a very simple way understand what mathematical procedures are conducted at what step of the processing pipeline. I find data-processing a bit confusing as both textbooks and inf... |
Nitric oxide is a tough molecule to represent as a Lewis structure. However, you have made one common mistake in your structures. I also want to clear up a misconception about resonance that's present in your post. Finally, I will need to introduce a different bonding picture of $\ce{NO}$ to answer your question about ... |
Why are borates more stable than aluminates? |
Phys.org's [Accelerating chemical reactions without direct contact with a catalyst](https://phys.org/news/2020-01-chemical-reactions-contact-catalyst.html) discusses the new Science Advances paper [Noncontact catalysis: Initiation of selective ethylbenzene oxidation by Au cluster-facilitated cyclooctene epoxidation](ht... |
What is it that makes this noncontact catalytic system unique and newsworthy in 2020? |
A sealed container contains 90% hydrogen and 10% oxygen. There is a spark in the container. What happens? |
Phys.org's [Accelerating chemical reactions without direct contact with a catalyst](https://phys.org/news/2020-01-chemical-reactions-contact-catalyst.html) discusses the new Science Advances paper [Noncontact catalysis: Initiation of selective ethylbenzene oxidation by Au cluster-facilitated cyclooctene epoxidation](ht... |
There is experimental data for the methoxy derivative: https://webbook.nist.gov/cgi/cbook.cgi?ID=C78289131&Units=SI&Mask=8
[![enter image description here][1]][1]
I think that means the (Z) form is favored. I would think the situation is similar in the absence of the methoxy group.
[1]: https://i.stack.imgur... |
Is it because citrate chelates calcium and then is unable to react with other chemicals being added? If so can someone explain this reaction to me, or if not provide what the reason is? If anyone has any studies they've found on it that would be incredibly helpful! Thank you! |
Why does Calcium (specifically Calcium Carbonate) inhibit the Citrate buffer system? |
what is the difference between
[![enter image description here][1]][1] and
[![enter image description here][2]][2]
[1]: https://i.stack.imgur.com/6LXUa.png
[2]: https://i.stack.imgur.com/jRKRk.png
how can I tell which one is the stronger acid, base on the 2 equations?
|
How to tell if an acid disassociate completely or partially? |
A sealed container contains 90 % hydrogen and 10 % oxygen. There is a spark in the container. What happens?
Assuming it is a 10-litre volume container like a fuel tank. |
A sealed container contains 90 % hydrogen and 10 % oxygen. There is a spark in the container. What happens? |
I have tried to search for this to little effect - I am trying to find electrical and thermal conductivity values for Electrum (a gold and silver alloy). Most sites mention the values depend on the percentage of gold and silver in the alloy, but provide no actual figures.
Is there a table out there that shows approx... |
Those carbocations are termed as 'stable' as the O/N atom establishes a '2p-2p back bond' with the empty p orbital on the carbon atom carrying the positive charge. This helps the carbocation stabilize as the O/N atom shares its electron density to the starving cation. This effect is FAR more dominating than the pulling... |
**Background**: I am trying to get an overview of the data-processing pipeline for solving protein structures by x-ray crystallography, and in a very simple way understand what mathematical procedures are conducted at what step of the processing pipeline. I find data-processing a bit confusing as both textbooks and inf... |
According to Wikipedia Etard reaction proceed via a ene reaction with chromyl chloride forming a Etard complex(Chromium complex) which is then decomposed by a [2,3] sigmatropic shift to give aldehyde.
[![enter image description here][1]][1]
But the reaction given in my textbook is as follows,
[ discusses the new Science Advances paper [Noncontact catalysis: Initiation of selective ethylbenzene oxidation by Au cluster-facilitated cyclooctene epoxidation](ht... |
What is it that makes this noncontact catalytic system unique in 2020? |
Why is the voltage produced by a voltaic cell affected by temperature as described by the Nernst Equation? |
Bare with me here, Im a GCSE student without much expertise so Im probably missing some key info out.
So as Ive been told, when a substance melts, the actual bonds of the substance arent broken, only the IMFs(intermolecularforces). So why is it that metal groups decrease in melting points going down when they should... |
Bear with me here, I'm a GCSE student without much expertise so I'm probably missing some key info out.
So as Ive been told, when a substance melts, the actual bonds of the substance aren't broken, only the IMFs (inter-molecular forces). So why is it that metal groups decrease in melting points going down when they ... |
I performed the iodine spectrum experiment to observe vibronic transitions. I heated the iodine crystals to produce vapors (at a little above room temperature) and observed absorption spectrum with a diffraction grating and a spectrometer. But I am getting some quirky results as indicated following.
1. In [Ref 1][1]... |
What is happening here in my iodine spectrum experiment? |
Many articles and books classify virus as a non living thing which only replicate itself inside a living host, yet some describe virus as a living organism. Virus was first discovered on the year 1892 by Dmitry Ivanovsky and Martinus Beijerinck. Since the year it was discovered, virus has different source of it's forma... |
Many articles and books classify virus as a non living thing which only replicate itself inside a living host, yet some describe virus as a living organism. Virus was first discovered on the year 1892 by Dmitry Ivanovsky and Martinus Beijerinck. Since the year it was discovered, virus has different source of it's forma... |
First, viruses are formed in other cells by the chemical processes of those cells. [Viruses "hijack" the cell's means for reproducing viral RNA or DNA and for the protein coat of the virus.][1]
Second, define "alive"... there is some argument on whether a virus is living or not, so that depends on your definition.
... |
This is to supplement ron's answer. The positive charge is due to a deficit of electrons in that region, and that "electron hole" may be treated in many ways as if it is a particle (moving around due to certain rules, etc). Non-particle phenomena that functionally behave as particles are dubbed "[quasiparticles][1]", a... |
When I start studying electrochemistry, I learn the words “molten” and “aqueous”. I don't have a problem for “aqueous”, but I'm a little bit confused about “molten”.
For me, “molten” means melt, which means to become liquid from solid. But why do we say *molten* lead(II) bromide instead of *liquid* lead(II) bromide?... |
(2,4-Dinitrophenyl)hydrazine, a popular laboratory reagent is used to identify carbonyl compounds by forming 2,4-dinitrophenylhydrazones, which are often red or yellow colored precipitates.
[![enter image description here][1]][1]
Why is the specific 2 and 4 positions that cause precipitate formation with carbony... |
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